TY - JOUR
T1 - A Diazido Mannose Analogue as a Chemoenzymatic Synthon for Synthesizing Di-N-acetyllegionaminic Acid-Containing Glycosides
AU - Santra, Abhishek
AU - Xiao, An
AU - Yu, Hai
AU - Li, Wanqing
AU - Li, Yanhong
AU - Ngo, Linh
AU - McArthur, John B.
AU - Chen, Xi
PY - 2018/3/5
Y1 - 2018/3/5
N2 - A chemoenzymatic synthon was designed to expand the scope of the chemoenzymatic synthesis of carbohydrates. The synthon was enzymatically converted into carbohydrate analogues, which were readily derivatized chemically to produce the desired targets. The strategy is demonstrated for the synthesis of glycosides containing 7,9-di-N-acetyllegionaminic acid (Leg5,7Ac2), a bacterial nonulosonic acid (NulO) analogue of sialic acid. A versatile library of α2-3/6-linked Leg5,7Ac2-glycosides was built by using chemically synthesized 2,4-diazido-2,4,6-trideoxymannose as a chemoenzymatic synthon for highly efficient one-pot multienzyme (OPME) sialylation followed by downstream chemical conversion of the azido groups into acetamido groups. The syntheses required 10 steps from commercially available d-fucose and had an overall yield of 34–52 %, thus representing a significant improvement over previous methods. Free Leg5,7Ac2 monosaccharide was also synthesized by a sialic acid aldolase-catalyzed reaction.
AB - A chemoenzymatic synthon was designed to expand the scope of the chemoenzymatic synthesis of carbohydrates. The synthon was enzymatically converted into carbohydrate analogues, which were readily derivatized chemically to produce the desired targets. The strategy is demonstrated for the synthesis of glycosides containing 7,9-di-N-acetyllegionaminic acid (Leg5,7Ac2), a bacterial nonulosonic acid (NulO) analogue of sialic acid. A versatile library of α2-3/6-linked Leg5,7Ac2-glycosides was built by using chemically synthesized 2,4-diazido-2,4,6-trideoxymannose as a chemoenzymatic synthon for highly efficient one-pot multienzyme (OPME) sialylation followed by downstream chemical conversion of the azido groups into acetamido groups. The syntheses required 10 steps from commercially available d-fucose and had an overall yield of 34–52 %, thus representing a significant improvement over previous methods. Free Leg5,7Ac2 monosaccharide was also synthesized by a sialic acid aldolase-catalyzed reaction.
KW - carbohydrates
KW - chemoenzymatic synthesis
KW - glycosylation
KW - legionaminic acid
KW - sialic acid
UR - http://www.scopus.com/inward/record.url?scp=85042023235&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85042023235&partnerID=8YFLogxK
U2 - 10.1002/anie.201712022
DO - 10.1002/anie.201712022
M3 - Article
C2 - 29349857
AN - SCOPUS:85042023235
VL - 57
SP - 2929
EP - 2933
JO - Angewandte Chemie - International Edition
JF - Angewandte Chemie - International Edition
SN - 1433-7851
IS - 11
ER -